This invention relates generally to prevention of air pollution and, more specifically, to a method of treating a nitrogen oxides-containing gas for the removal of the nitrogen oxides therefrom.
Serious problems are now caused by air pollution, especially by nitrogen oxides (NO.sub.x) discharged from internal combustion engines, boilers, nitric acid-related industries, etc. One known technique for the treatment of an NO.sub.x -containing waste gas includes a step of contacting the waste gas with a solid catalyst, such as a proton-type mordenite, in the presence of an organic compound, such as propane, as a reducing agent. The known technique, however, is not fully satisfactory with respect to NO.sub.x reducing efficiency.